Auto merge of rust-lang#6661 - Manishearth:exhaustive-fix, r=flip1995

exhaustive_structs: don't trigger for structs with private fields

changelog: Restrict `exhaustive_structs` to structs with all-public
fields

Author: bors

clippy_lints/src/exhaustive_items.rs

@@ -75,10 +75,14 @@ impl LateLintPass<'_> for ExhaustiveItems {
             if cx.access_levels.is_exported(item.hir_id);
             if !item.attrs.iter().any(|a| a.has_name(sym::non_exhaustive));
             then {
-                let (lint, msg) = if let ItemKind::Enum(..) = item.kind {
-                    (EXHAUSTIVE_ENUMS, "exported enums should not be exhaustive")
-                } else {
+                let (lint, msg) = if let ItemKind::Struct(ref v, ..) = item.kind {
+                    if v.fields().iter().any(|f| !f.vis.node.is_pub()) {
+                        // skip structs with private fields
+                        return;
+                    }
                     (EXHAUSTIVE_STRUCTS, "exported structs should not be exhaustive")
+                } else {
+                    (EXHAUSTIVE_ENUMS, "exported enums should not be exhaustive")
                 };
                 let suggestion_span = item.span.shrink_to_lo();
                 let indent = " ".repeat(indent_of(cx, item.span).unwrap_or(0));

tests/ui/exhaustive_items.fixed

@@ -56,27 +56,36 @@ pub mod enums {
 pub mod structs {
     #[non_exhaustive]
     pub struct Exhaustive {
-        foo: u8,
-        bar: String,
+        pub foo: u8,
+        pub bar: String,
     }
 
     // no warning, already non_exhaustive
     #[non_exhaustive]
     pub struct NonExhaustive {
-        foo: u8,
+        pub foo: u8,
+        pub bar: String,
+    }
+
+    // no warning, private fields
+    pub struct ExhaustivePrivateFieldTuple(u8);
+
+    // no warning, private fields
+    pub struct ExhaustivePrivateField {
+        pub foo: u8,
         bar: String,
     }
 
     // no warning, private
     struct ExhaustivePrivate {
-        foo: u8,
-        bar: String,
+        pub foo: u8,
+        pub bar: String,
     }
 
     // no warning, private
     #[non_exhaustive]
     struct NonExhaustivePrivate {
-        foo: u8,
-        bar: String,
+        pub foo: u8,
+        pub bar: String,
     }
 }

tests/ui/exhaustive_items.rs

@@ -53,27 +53,36 @@ pub mod enums {
 
 pub mod structs {
     pub struct Exhaustive {
-        foo: u8,
-        bar: String,
+        pub foo: u8,
+        pub bar: String,
     }
 
     // no warning, already non_exhaustive
     #[non_exhaustive]
     pub struct NonExhaustive {
-        foo: u8,
+        pub foo: u8,
+        pub bar: String,
+    }
+
+    // no warning, private fields
+    pub struct ExhaustivePrivateFieldTuple(u8);
+
+    // no warning, private fields
+    pub struct ExhaustivePrivateField {
+        pub foo: u8,
         bar: String,
     }
 
     // no warning, private
     struct ExhaustivePrivate {
-        foo: u8,
-        bar: String,
+        pub foo: u8,
+        pub bar: String,
     }
 
     // no warning, private
     #[non_exhaustive]
     struct NonExhaustivePrivate {
-        foo: u8,
-        bar: String,
+        pub foo: u8,
+        pub bar: String,
     }
 }

tests/ui/exhaustive_items.stderr

@@ -41,8 +41,8 @@ error: exported structs should not be exhaustive
   --> $DIR/exhaustive_items.rs:55:5
    |
 LL | /     pub struct Exhaustive {
-LL | |         foo: u8,
-LL | |         bar: String,
+LL | |         pub foo: u8,
+LL | |         pub bar: String,
 LL | |     }
    | |_____^
    |